updated: January 30, 2008

Photo Gallery Included below are figures referred to elsewhere on this Web site, as well as additional images representative of Biological Soil Crusts on the Colorado Plateau. TIF downloads are available for some images. All TIFs are roughly 3.5" x 5" at 300dpi and are quaranteed royalty-free.

Figure 1 - Open spaces covered by biological soil crusts, a highly specialized community of cyanobacteria, mosses, and lichens. View larger version	Figure 2 - Arid ecosystems in the United States where crusts are found. View larger version
Figure 3 - Mature crusts of the Colorado Plateau. View larger version Download 4MB TIF file	Figure 4 - Undisturbed crusts on the Colorado Plateau are usually darker than the disturbed soils. View larger version Download 4MB TIF file
Figure 5 - Crusts generally cover all soil spaces not occupied by vascular plants, which may be 70% or more of the living cover. View larger version Download 4MB TIF file	Figure 6 - Filamentous cyanobacteria migrating out of their sheaths, x950. View larger version Download 1.6MB TIF file
Figure 7- Mature crust in the Mojave desert. View larger version Download 4MB TIF file	Figure 8 - Soil cyanobacteria can either be on, or beneath, the soil surface. View larger version Download 4MB TIF file
Figure 9 - Soil mosses and lichens found on crust. View larger version	Figure 10 - Scanning electron micrograph of cyanobacterial sheath material, sticking to sand grains, x90. View larger version Download 1.5MB TIF file
Figure 11 - Scanning electron micrograph of cyanobacterial sheath material, holding sand grains together, x100. View larger version Download 1.4MB TIF file	Figure 12 - Cyanobacterial sheath material holding soil particles together. View larger version Download 4MB TIF file
Figure 13 - Steep slope held in place by crusts. View larger version	Figure 14 - Soils less than 6" deep, held in place by crusts. View larger version Download 5MB TIF file
Figure 15 - Top: Roughened soil surfaces slow the velocity of water runoff, resulting in longer residence times. Longer residence times increase water infiltration into the soil. Bottom: Smooth surfaces do not slow runoff water, and thus infiltration is decreased relative to rough surfaces. View larger version	Figure 16 - Compressional disturbances crushes crusts, leaving soils underneath them unprotected from wind or water erosion. View larger version
Figure 17 - Removal of crust can lead to large soil losses, as seen here in the Channel Islands. View larger version	Figure 18 - Disturbance to soil surfaces in arid regions can result in large amounts of soil loss. Here, soil levels are now several feet below what they were when this tree was alive. View larger version
Figure 19 - Blowing or washing sand buries crusts, killing them. View larger version Download 4MB TIF file	Figure 20 - Cyanobacterial thickness 5 years after disturbance. Thickness increases about 1 mm/year. View larger version
Crust Logo - Spread the word...Don't Bust The Crust! Print size of TIF file is 3" x 3". View larger version Download 1MB TIF file	Image 1 - Closeup of biological soil crust. View larger version Download 4MB TIF file
Image 2 - Closeup of seedling in biological soil crust. View larger version Download 4MB TIF file	Image 3 - Landscape with healthy soil crusts. View larger version Download 4MB TIF file
Image 4 - Biological soil crusts can be monitored using visually defined categories in areas dominated by cyanobacteria. These six categories were chosen for the Colorado Plateau. Tests showed these categories are easily distinguished by both trained and untrained observers and are closely related to cyanobacterial biomass and the resistance of the soil surface For more information, see Belnap, J., S. L. Phillips, D. L. Witwicki, and M. E. Miller. In press. Visually assessing cyanobacterial biomass and soil surface stability in cyanobacterially dominated biological soil crusts. Journal of Arid Environments. View larger version Download 8MB TIF file
USGS Canyonlands Research Station Southwest Biological Science Center 2290 SW Resource Blvd Moab, UT 84532 (435)719-2331 info@soilcrust.org